Quelling the Unrest is a repeatable quest that marks the end of Bortinthas' quest line. Aside from that you should have 2 other quest lines -- one from Ber'Tanos and one from Platos. They too end in repeatable quests.
But yeah, once you finish all three it's pretty much PvP and sieging NPCs. Or you can always start a new race/city.
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